Dookhan sent the state’s criminal justice system into a tailspin in 2012 when state police shut down the state Department of Public Health lab she worked at in Jamaica Plain after discovering the extent of her misconduct.

Prosecutors said Dookhan admitted “dry labbing,” or testing only a fraction of a batch of samples, then listing them all as positive for illegal drugs, to “improve her productivity and burnish her reputation.”

Once the lab closed in August 2012, at least 1,100 criminal cases were dismissed or not prosecuted because of tainted evidence or other fallout from the lab’s shutdown.